Are some people more attractive to mosquitoes?

Yes, certain traits can attract or repel mosquitoes.

Yes they do, says Dr Cameron Webb from Westmead Hospital's department of medical entomology in Sydney. And although the reasons behind their preferences are far from certain, it's likely to do with the chemicals in our breath and on our skin.

Why the difference?

Female mosquitoes are primarily attracted to our body heat and the carbon dioxide we breathe out, which indicate we are warm-blooded animals with the blood they need to develop fertile eggs.

So the more carbon dioxide we emit, the more attractive we are to females looking for a protein hit. (Male mosquitoes don't bite).

Larger people tend to emit more carbon dioxide than smaller people, as do pregnant women and those who exert themselves.This is why we are often annoyed most by mosquitoes after we play sports and are breathing heavily.

Mosquitoes are also attracted to different chemicals on our skin, Webb says.

"When mosquitoes get close to a person they make a decision on whether they bite or not based on essentially the smell of our skin, and that smell can vary from person to person because of different combinations of chemicals on the skin," he says.

However, researchers are still uncertain which chemicals mosquitoes find attractive.

Hairy arms or legs can be a physical deterrent to mosquitoes, Webb says, and the type of deodorant or perfume you wear possibly has a role in how attractive you smell to the pests.

Evidence also shows wearing dark colours such as black and navy can attract mosquitoes, perhaps because they tend to trap rather than repel heat like lighter colours.

It's also worth remembering that some people have a greater reaction to mosquito bites than others, making it seem as if they are being bothered more than other people.

Remedies

Contrary to popular belief, there is no scientific evidence that eating bananas or other foods containing vitamin B repel mosquitoes, Webb says.

The gold standard insect repellent is N,N-Diethyl-m-toluamide, commonly abbreviated to DEET, which switches off the mosquitoes' desire to ingest blood. When you use DEET you will sometimes notice mosquitoes hovering but not biting.

"Even the lowest doses can provide at least a couple of hours of protection against biting mosquitoes, and that's certainly two hours longer than any home remedy I am aware of," he says.

Botanical products that contain citronella, eucalyptus oil or melaleuca oil do repel mosquitoes, but only for very short period of time, and you have to reapply four times as frequently as a low-dose DEET-based repellent, Webb says.

Dr Cameron Webb PhD is a clinical lecturer at the University of Sydney and hospital scientist at Westmead Hospital's department of medical entomology, Sydney. He spoke to Jenny Pogson.

http://www.abc.net.au/health/talkinghealth/factbuster/stories/2011/11/30/3379114.htm